Three Victorians with dry age-related macular degeneration (AMD) have undergone pioneering gene therapy surgeries to trial an experimental treatment for their eye disease.
The patients are part of Australia's first clinical trials of an investigational gene therapy for a form of AMD known as dry AMD or geographic atrophy.
Their involvement is also contributing to important research into the disease - for which there is currently no treatment or cure.
The patients are part of the Phase II clinical trials - HORIZON and EXPLORE - testing the safety and effectiveness of an investigational gene therapy developed by UK company Gyroscope Therapeutics.
CERA Principal Investigator of Retinal Gene Therapy and vitreoretinal surgeon Dr Tom Edwards performed the first surgeries to deliver the investigational gene therapy between March and May this year.
Over the next 18 months, up to 20 patients are expected to receive the investigational treatment as part of the trials.
About AMD
AMD occurs when debris develops in the central retina (or macula), the tissue responsible for taking light and turning it into vision. Over time the cells in the retina slowly die leaving gaps, or holes, in the vision.
About one in seven Australians over 50 has the early signs of AMD, in stages called early and intermediate AMD. These stages can lead to severe vision loss if they progress to the late stage of the disease.
There are two forms of late stage disease - wet and dry. Wet is where blood vessels bleed in the back of the eye.
Dry AMD, the other form of late stage AMD, is an irreversible degeneration of retinal cells, causing a gradual and permanent loss of central vision.
Research has led to the development of treatments which can effectively manage the wet form of AMD but there are no treatments for the dry form of late AMD.
CERA's Principal Investigator of Retinal Gene Therapy Dr Tom Edwards says it can be a devastating diagnosis.
"In the advanced, late stage form of AMD, it can rob people of their ability to read, drive or even see the faces of loved ones,'' says Dr Edwards.
Investigational Gene Therapy
The investigational therapy aims to introduce a corrective gene to dampen overactivity in a part of the immune system that has been linked to inflammation and damage to healthy eye tissue.
The investigational product consists of a non-infectious virus that acts as a delivery vehicle for the gene therapy to the correct area of the eye.
It is administered in an operating theatre, using a canula as thin as a human hair to deliver a small amount of fluid containing safe viral particles filled with the corrective gene underneath the retina.
To ensure maximum precision, a foot pedal and advanced microscopy equipment is used to guide the canula into position.
After the surgery, patients' vision will be monitored by CERA's clinical researchers and undergo a series of rigorous visual assessments throughout the trial period.
An eye on the future
Dr Edwards says the current collaboration between CERA and the Eye and Ear,
highlights Melbourne's unique mix of infrastructure, clinical and research skills for ocular gene therapy.
"It's an exciting time for patients, researchers and clinicians. The collaborative relationships here in Melbourne provide a great example of Victoria and Australia's potential to become a world leader in developing and trialling gene therapies to prevent vision loss and blindness,'' he says.
"We have a specialist eye hospital in the Eye and Ear, a world top-five eye research institute in CERA and the nation's highest concentration of biomedical researchers and biotech companies."
